Chordate Zoology - Textbook - I. V. Tsaryk - 2013

Chapter 5. SUPERCLASS TETRAPODS (TERRESTRIAL VERTEBRATES) TETRAPODA, seu QUADRIPEDA.

ANAMNIANS (ANAMNIA) AND AMNIOTES (AMNIOTA)

5.3. CLASS BIRDS AVES

5.3.3. Taxonomy and characteristics of representatives of the main orders of the class Aves

5.3.3.2. Superorder Typical, or Neognathous Birds Neognathae

5.3.3.2.9. Order Pelicaniformes Pelecaniformes

Morphologically diverse waterbirds with all four toes united by a web. There are 50 (67) species in total. Their bills vary greatly in shape, and their plumage is dense and tightly adhering. Sexes are similar in coloration. Flight patterns vary across groups, ranging from slow to swift and highly maneuverable.

They walk slowly and awkwardly on land, though they are strong swimmers. Some species dive exceptionally well, while others plunge-dive. They are monogamous. They nest in colonies ranging from tens to thousands of pairs on marine coasts or near large freshwater bodies. Nests are built on the ground, rock ledges, or trees. The clutch contains one to six eggs, which are incubated by both parents. Chicks hatch blind and altricial (downless), remaining in the nest for 6-15 weeks until they fledge. The parents feed the young. After fledging, the juveniles roam with their parents. Food is acquired in Water.

The Great White Pelican Pelecanus onocrotalus is a large bird weighing 9-14 kg, featuring a long, flattened bill and a gular pouch suspended from the lower Mandible rami (Fig. 5.45, 10). It feeds on fish scooped up using its pouch. It is a slow flyer and a strong swimmer, but does not dive.